docs: update top-models telemetry dates to June 1, 2026

Bumps the Top models (YTD) range and last-updated stamp to match the refreshed figure's data snapshot (year-to-date through 6/1/2026).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Eric W. Tramel <eric.tramel@gmail.com>

Author: eric-tramel

README.md

@@ -153,11 +153,11 @@ Disable with `NEMO_TELEMETRY_ENABLED=false`. **[More details →](#telemetry-and
 
 ### Top models (YTD)
 
-Aggregate model usage across synthetic data generation jobs, year-to-date 1/1/2026–5/1/2026:
+Aggregate model usage across synthetic data generation jobs, year-to-date 1/1/2026–6/1/2026:
 
 ![Top models used for synthetic data generation](docs/images/top-models.png)
 
-_Last updated on May 1, 2026_
+_Last updated on June 1, 2026_
 
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